Electromechanical-type disc brake caliper comprising two mechanical actuators to compensate for an uneven wearing of the one same brake pad

Abstract

A brake caliper comprising: a set of brake pads positioned on each side of a brake disc; a first actuator including a first drive gearwheel driving a first mobile piston pressing against a first portion of brake pad in order to move same; a second actuator including a second drive gearwheel driving a second mobile piston pressing against a second portion of the pad in order to move same, with a mode of operation that is the opposite of that of the first actuator; a first and a second worm screws which are secured to one another and of opposite hand to one another, rotationally driven and capable of translational movement in their longitudinal direction and in mesh with the first and second gearwheels respectively in order to turn these in opposite directions.

What is claimed is: 
     
       1. A brake caliper for overlapping a brake disc, comprising:
 a set of pads; and 
 an electromechanical actuator for pressing a pad of the set of pads, wherein the electromechanical actuator comprises:
 a first mechanical actuator including a first drive gear and a first piston for pressing a first portion of the pad, the first mechanical actuator converting a rotation of the first drive gear into a translation of the first piston; 
 a second mechanical actuator including a second drive gear and a second movable piston for pressing a second portion of the pad, the second mechanical actuator converting a rotation of the second drive gear into a translation of the second piston, the first and second mechanical actuators having reverse conversion senses; 
 an electric motor driving the first mechanical actuator and the second mechanical actuator; and 
 a transmission module comprising:
 a first worm screw and a second worm screw having a same longitudinal direction and having reverse winding senses while being rigidly connected to each other, these first and second worm screws being meshed with the first and second drive gears respectively to simultaneously rotate them in reverse senses; and 
 means for rotatably driving the first and second worm screws by the electric motor, these means including splines and forming a slider enabling the first and the second worms to translationally move along the longitudinal direction. 
 
 
 
     
     
       2. The brake caliper according to  claim 1 , wherein the means for rotatably driving the worm screws of the transmission module includes:
 a rotary shaft rigidly carrying the first and second worm screws, this shaft being translationally movable along the longitudinal direction; and 
 a translationally fixed gear rotated by the electric motor, this gear comprising a splined through hole in which a splined end of the shaft is engaged, 
 wherein the splines of the means for rotatably driving the first and second worm screws are defined by the splined through hole of the translationally fixed gear and the splined end of the rotary shaft. 
 
     
     
       3. The brake caliper according to  claim 1 , wherein the means for rotatably driving the first and second worm screws of the transmission module includes:
 a sleeve rigidly carrying the first and second worm screws, this sleeve being translationally movable along the longitudinal direction; 
 a translationally fixed gear rotated by the electric motor; 
 a rotary shaft including external splines, the rotary shaft being rigidly connected to and projecting from the gear, this rotary shaft extending along the longitudinal direction and being surrounded by the sleeve; and 
 internal splines carried by the sleeve with which the external splines mesh by form fitting, 
 wherein the splines of the means for rotatably driving the first and second worm screws include the internal splines of the sleeve and the external splines of the rotary shaft. 
 
     
     
       4. The brake caliper according to  claim 3 , wherein the internal splines project from a hub rigidly connected to the sleeve. 
     
     
       5. The brake caliper according to  claim 1 , wherein the first and second drive gears have oblique teeth and rotate about axes parallel to each other and perpendicular to the longitudinal direction. 
     
     
       6. The brake caliper according to  claim 1 , further comprising a reduction module which transmits rotation of the motor to the means for rotatably driving the first and second worm screws. 
     
     
       7. A disc brake, comprising the brake caliper according to  claim 1 . 
     
     
       8. The brake caliper according to  claim 6 , wherein the reduction module includes an oblique-tooth idler gear and an epicyclic gear train, wherein the idler gear meshes with a motor pinion gear and the epicyclic gear meshes with the transmission module. 
     
     
       9. The brake caliper according to  claim 8 , wherein the transmission module includes an angle transmission gear meshing with an output pinion gear at an output of the epicyclic gear train. 
     
     
       10. A brake caliper for overlapping a brake disc, the brake caliper comprising:
 a first pad for pressing against a first face of the disc; 
 a first mechanical actuator including a first drive gear and a first piston for pressing a first portion of the first pad, the first mechanical actuator converting a rotation of the first drive gear into a translation of the first piston; 
 a second mechanical actuator including a second drive gear and a second movable piston for pressing a second portion of the first pad, the second mechanical actuator converting a rotation of the second drive gear into a translation of the second piston; 
 an electric motor driving the first mechanical actuator and the second mechanical actuator; and 
 a transmission module comprising:
 a first worm screw and a second worm screw having a same longitudinal direction and being rigidly connected to each other, these first and second worm screws being meshed with the first and second drive gears respectively to simultaneously rotate them; 
 a rotary shaft rigidly carrying the first and second worm screws; and 
 a translationally fixed gear rotated by the electric motor, the rotary shaft being coupled to the gear by splines such that the rotary shaft is rotationally fixed relative to the gear and translationally movable relative to the gear along the longitudinal direction. 
 
 
     
     
       11. The brake caliper according to  claim 10 , wherein:
 the first and second mechanical actuators have reverse conversion senses, 
 the first and second worm gears have reverse winding senses, and 
 first and second worm screws are meshed with the first and second drive gears respectively to simultaneously rotate them in reverse senses. 
 
     
     
       12. The brake caliper according to  claim 10 , further comprising:
 a second pad for pressing against a second face of the disc opposite to the first face; and 
 a caliper body that carries the first pad and second pad. 
 
     
     
       13. The brake caliper according to  claim 12 , wherein the first and second mechanical actuators are arranged on a same side of the first and second pads and are operable to press both the first and second pads against the disc. 
     
     
       14. The brake caliper according to  claim 1 , wherein the brake caliper is a floating brake caliper. 
     
     
       15. A disc brake comprising the floating brake caliper according to  claim 14 .